An electromagnetic fuel injection valve is known from, for example, Patent Document 1, in which a large diameter hole is coaxially provided in a front portion of a cylindrical magnetic body so as to form an annular step portion facing forward, a ring-shaped stopper for restricting a moving end of a valve body on the side on which the valve body separates from a valve seat is inserted into the large diameter hole so as to abut against the annular step portion, a rear portion of a valve seat member is press-fitted into the large diameter hole so that the rear end of the rear portion abuts against the stopper, and corner portions formed from the front end of the cylindrical magnetic body and the outer periphery of the valve seat member are welded together along the entire periphery.
Patent Document 1:
Japanese Patent Application Laid-open No. 2002-89400